| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 755.1 | no difference ... | NETRIX::"srn@rio.zk3.dec.com" | | Mon Feb 10 1997 18:34 | 8 |
| Earlier versions of VxVM, which LSM is based upon, did not have support
or the notion of diskgroups -- all special device files were in just
/dev/[r]vol. As a result, volumes in rootdg, the default diskgroup, get
special device files created in both /dev/[r]vol and the diskgroup's
directory (i.e., /dev/[r]vol/rootdg) for compatibility reasons.
[Posted by WWW Notes gateway]
|
| 755.2 | interchangeable block special files? | DOOSJE::HERTA | For something fulfilled this hour, loved, or endured | Tue Feb 11 1997 09:25 | 13 |
| Re.:.1
Thanks for your answer.
In the Logical Storage Manager manual for DEC OSF/1 V3.2 p. 8-31 instructions
are to add the secondary swap space in /etc/fstab using
/dev/vol/rootdg/swapvol1, and then to add the swap space to the running system
by means of the command "# swapon /dev/vol/swapvol1". If the files can be used
interchangeably, that would explain why both instructions work.
However, the files look different to me because they have different inodes.
Apparently, I misunderstand block special files. How does it work?
Herta
|
| 755.3 | | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Tue Feb 11 1997 20:34 | 14 |
| Special files contain two pieces of information to tell the
system how they are to be handled; a bit to indicate whether
the the file is for a character device or block device and
a device number. The device number is in two parts, the major
device number that indicates which driver to use and the minor
device that is used by that driver to identify which specific
device.
When one of the special file bits is set, the system call
handling code uses a special device "file system" set of
calls to handle the details of open/close/read/write/ioctl
and so on. So, as long as the two individal files refer
to the same special file type and device number, everything
works right inside the kernel.
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| 755.4 | thanks for explaining | DOOSJE::HERTA | For something fulfilled this hour, loved, or endured | Thu Feb 13 1997 13:57 | 0
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